Gun-tube and method of manufacturing same



A. E. GUY. GUN TUBE AND METHOD OF MANUFACTURING SAME. APPLICATION FILED SEPT. 2. I919.

1,384,? 1 8. Patented July 12, 1921.

INVENTOR I UNITED STATES ALBERT n. GUY, OETHE UNITED STATES ARMY.

' GUN-TUBE AND METHOD or MANUFACTURING SAME 7 Specification of Letters Patent. Patntcl July 12, 1921.

Application filed-September 2, 1919. Serial No. 321,225.

(FILED man-runner or nnncn s, 1883, 22: STAT. 1).,625.

To all whom it may concern: j

Be it known that I, ALBERT E. GU major, Ordnance Department, United States Army, a citizen of the United States,- stationed at Washington, D. C., have invented an Improvement in Gun-Tubes and Method of Manufacturing Same, of which the following is a specification;

The invention described herein maybe used by the Government, or any of its officers or employees in prosecution of work for the Government, or by any other person in the United States, without payment of any royalty thereon.

ThlS invention relates to improvements in the manufacture of gun tubes and more especially to the method of boring same, whereby the natural droop of the gun will be counteracted, or compensated for, so that the axis of the bore of the gun will be straight when the gun is mounted in position for firing.

Owing to the length of the modern gun tube, and method of mounting same, a droop or depression of the outer unsupported ends of the tube due to its weight, causes a curvature of the bore. 1

When the gun is fired the droop of the gun and consequent curvature in the bore causes molecular vibrations in the material of the gun tube and the beats thus occasioned, force the hard steel of the body of the projectile into the rifling grooves of the tube.

The contact between the parts as above referred to, not only reduces the range of the gun but destroys its accuracy, said contact being of sufiicient force to cause the surface of the projectile to be embedded in the rifling grooves, thus scoring the surface of the shell in such a manner as to further retard its progressafter it leaves the gun.

The contact above referred to, damages the rifling to such an extent that it is rendered useless, and if the gun has been relined, causes a drag so intense that the lining is caused to creep to an unusual degree, and thereby reduces the life of the gun.

Similar numerals indicate corresponding parts in all the figures of the drawings in which Figure 1 is a side view of a modern rifle barrel and its support, showing in full lines the natural droop of the gun and in dotted lines the curvature of the bore. dot and dash-linesthe gun is shown without its natural droop.

vF'g. 2 is a side view'of the inner tube of the gun, supported at its ends to bend same as when mountedfor firing. In dotted lines,

the bore is shown bored on -a straight axis.

Fig; 3 isa viewjsimilar-to Fig. 1 showing.

the gun having its nautral droopand the bore one. true axis or straight line.

Referring to the drawings by numerals 1 indicatesthe gunltube', 2,-theouter jackets anfld 3 the mount of a modern long range r1 e. The gun is usually mounted at the balancing point, which is in rear of its center owing to the relative thickness of the gun tube at the breech and muzzle. ing of the gun at one point is necessary for convenience in elevating and traversing the gun in aiming. Y

Mounting the gun at one point in its length, supports its entire weight with one- Said mount- 7 half thereof in front and one-half in rear of said point free for depression under the influence of gravity, and it is due to the above conditions that a droop in the gun is the result. v

While all lengths of guns have more or less droop, the development of the modern coast defense or other long range rifle has increased the droop in the gun and the damage due to beating caused. by vibration.

. The high velocity of the projectile through said type of gun, also increases the damage due to droop.

The projectile in its passage through the gun, tends to travel in a straight line, and owing to the curvature of the bore due to vibrated or whipped from its initial or natural position in relation to the line of travel of the projectile to a position opposite to the natural droop of the gun, the same issaid position and back again durlng the gun, prior to applying the outer sleeves, on

supports l-4c (see Fig. 2,) said supports so located and the gun tube so arranged as to place in the tube an artificial bend, identical to that caused by the natural droop, of the gun when mounted ready for firing.

With the tube in the position above described, it is bored 'and'rifled on a true or perfectly straight line; V or 1 w When the tube is removed from the supports 4-4 and supported throughout its entire length, the axis of the gun Willfigain assume a straight line and the bore with its rifling, which had been bored on a straight axis, will assume a curved line equal to 'or corresponding with the natural droop of the gun if mounted inthe usual Way for firing, but in an opposite direction.

Therefore when thegun is mounted, the

tube will sag or 'droop and the bore will becomestraight. i

For convenience the tube, when positionedfor boring as shown in Fig. 2, is inverted from the position it will occupy when mounted, and should it be necessary any preferred pressure means (not shown) may "be employed to produce said artificial bend.

Having described my invention, what I claim as new and desire" to secureiby Letters Patent, isa- I a a v 1. The method of manufacturinga tube, consistingjof :forming a tube on a true line, springing a tube out of a true line and boring and 'rlfling-f 2. The method of manufacturing a gun tube, consisting of bending the tuh'efin 'a di rection of its natural droop 'vvhen mounted and=boringl s. The method' of manufacturing a gun tube, consisting of bending the' tube in the same direction and to' the samee'xtent as its natural droop when mounted and bearing:

4. A gun tube, theaxis'ofi'theboreof which is straight when the tube isfflexed an amount equal to that due to droop.

ALBERT E1 GUY, 

